In the current mold fabrication techniques, the hot pressing techniques are typically applied to the fabrication of shoe soles. After selecting the appropriate mold for the fabrication of a shoe sole, a mixture of foaming agent is added and heated, and the sole is formed after the mold is cooled. Hence, the temperature control of the mold in the hot pressing process is an important controlling factor.
Presently, the heating of a shoe sole mold is via a hot plate, wherein the shoe sole mold is placed on a hot plate with a hot liquid tunneling through and the shoe sole mold is heated via heat conduction. However, relying the conduction method for heat conduction is time consuming. Further, the surface of the mold, used in hot pressing, is closer to the hot plate, and that surface of the mold is heated faster than other areas of the mold, resulting in an overall uneven heating. Furthermore, the heat emitted from the hot plate does not absorbed solely by the neighboring regions of the hot pressed surface. Consequently, power consumption is increased.
The current technology further includes directly incorporating a heating unit in the mold. However, such a mold necessitates a reconnection of the wirings of the hot plate when the mold is being replaced; hence, the mold replacement process becomes more complicated. Further, incorporating a heating unit in the mold increases the fabrication cost and the removable heating pipelines also present safety issues.